AT&T reveals cause of massive outage — says it was not a cyberattack

 AT&T logo.
AT&T logo.

A nationwide cellphone outage that affected hundreds of thousands of customers on Thursday was the result of an error not a cyberattack, AT&T has revealed.

AT&T customers woke up to find they couldn’t make phone calls or access the internet and this continued through to early afternoon before the service was finally restored.

A spokesman for the company said it was the result of an error made while expanding the network and that they would continue to assess the issue.

What exactly happened?

Based on our initial review, we believe that today's outage was caused by the application and execution of an incorrect process used as we were expanding our network, not a cyber attack.

The first reports started coming in early in the morning, with some 70,000 customers taking to outage reporting website Downdetector to express concern.

Issues with access continued throughout the morning on the East Coast, although there were hot spots of reported issues in Atlanta, Chicago, Dallas, Houston and Los Angeles.

While there were also reports from a number of other operators including Verizon and T-Mobile, those issues seem to have been tied to trying to reach AT&T customers.

Fortunately, AT&T's network outage wasn't an extended one. By the late afternoon, the company released a statement saying that its service was fully restored. Although, the cause of the network outage was still unknown — prompting the FCC to look into the matter.

What was the problem?

At the height of the outage there were speculation over the cause with some suggesting a potential cyber attack or even a solar flare. While these are normally harmless, solar flares have the potential to significantly disrupt cellular communications.

National Security Council spokesman John Kirby said both the FBI and Department for Homeland Security were looking into the outage.

The specific details are fairly limited from AT&T but the company says network expansion efforts led to an error and this caused the mass outage on Thursday.

AT&T finally issued a short statement explaining: “Based on our initial review, we believe that today's outage was caused by the application and execution of an incorrect process used as we were expanding our network, not a cyber attack.”

Adding: “We are continuing our assessment of today’s outage to ensure we keep delivering the service that our customers deserve.”

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